Abstract

Patients and Methods: Preoperative serum tumor markers including CEA, CA19-9 and p53 antibody were examined in 264 patients (stage I: 68, II: 73, III; 81) who were given diagnoses of colon and/or rectal cancer in Yokohama City University Hospital from 2007 to 2008. Correlativity of tumor markers to clinical findings was investigated.

Results: In the overall patients, range, median and positive ratio of each tumor marker are shown in Table 1. Positive ratio of CEA and CA19-9 gradually increased according to clinical stage of the tumor, however, those of p53 showed almost the same concentration in any stage. Then, in stage I patients, positive ratio of p53 was higher than CEA and CA19-9 (p=0.0005).

Thirty five cases (13.3%) of patients had synchronous or metachronous double or triple colorectal cancers. In that group, positive ratio of p53 was 48.3%, and median serum concentration of p53 was 0.915U/ml (0.15-295). Positive ratio and serum concentration of p53 of double or triple colorectal cancer patients were significantly higher than that of single cancer patients (p=0.0375).

Conclusions: Serum concentration of p53 is sensitive, especially in early stage of colorectal cancer compared with other tumor markers. Colorectal cancer patients who showed high concentration of p53 have to be carefully checked for occult 2nd gastrointestinal tumor.